mattercontrol/research/11-print-queue-history.md

Print Queue & History

Summary

MatterControl maintains print job history for tracking completed prints, managing queued items, and enabling print recovery after failures. The system stores print metadata, tracks progress, and provides analytics on print success rates.

Technical Description

Architecture

Print Management
├── Print Queue (FileSystemContainer)
│   └── Queued items for printing
├── Print History (PlatingHistoryContainer)
│   └── Completed/cancelled prints
└── PrintTask (database records)
    └── Print job metadata

PrintTask Entity

Database model for print jobs:

public class PrintTask : Entity
{
    public string PrintName { get; set; }
    public DateTime PrintStart { get; set; }
    public DateTime PrintEnd { get; set; }
    public int PrintTimeSeconds { get; set; }
    public double PercentDone { get; set; }
    public bool PrintComplete { get; set; }
    public string PrinterName { get; set; }
    public string RecoveryJson { get; set; }
    public int QualityWasSetByUser { get; set; }
}

Print Queue

Legacy queue system using file system container:

Class	Purpose
LegacyQueueFiles	Queue directory management
FileSystemContainer	Queue item storage

Queue directory: {ApplicationData}/Queue/

History Container

PlatingHistoryContainer provides access to print history:

Feature	Description
NewBedPlate()	Create new print session
Content storage	Save print bed state
History browsing	Access past prints

Print Tracking Flow

1. Print Start:

   • Create PrintTask record
   • Set PrintStart timestamp
   • Initialize progress to 0%

2. During Print:

   • Update PercentDone
   • Save recovery data (RecoveryJson)

3. Print Complete:

   • Set PrintEnd timestamp
   • Calculate PrintTimeSeconds
   • Set PrintComplete flag

4. On Cancel:

   • Record partial completion
   • Preserve recovery data

Print Recovery

Recovery enables resuming failed prints:

// PrintRecoveryStream handles recovery
public class PrintRecoveryStream : GCodeStream
{
    // Track position and extrusion
    // Resume from last known good position
}

Recovery Data:

• Last printed layer
• Current position (X, Y, Z)
• Extruded amount
• Temperature states

History Display

RootHistoryContainer shows print history:

History
├── Printing History (PrintTask records)
│   ├── Print date/time
│   ├── Print duration
│   ├── Printer used
│   └── Completion status
└── Plating History
    └── Saved bed configurations

Statistics Tracking

Metric	Storage
Total print count	ApplicationSession.PrintCount
Print duration	PrintTask.PrintTimeSeconds
Success rate	Calculated from PrintComplete

Events

Event	Source	Description
PrintStarted	PrinterConnection	Print begins
PrintFinished	PrinterConnection	Print completes
AnyPrintStarted	ApplicationController	Global start event
AnyPrintComplete	ApplicationController	Global complete event

Design Rationale

Database Storage: Using SQLite for print tasks enables:

• Persistent history across sessions
• Query capabilities (by date, printer, etc.)
• Recovery data preservation

File-Based Queue: The queue uses file system for:

• Simple item management
• Visual thumbnails
• Easy user access to files

Recovery System: Saving print state allows:

• Resume after power failure
• Continue after software crash
• Re-slice and continue

Reference

Core Classes

Class	Location	Description
PrintTask	DataStorage/Models.cs	Print job record
PrintHistory	PrintHistory/	History UI
LegacyQueueFiles	PrintQueue/LegacyQueueFiles.cs	Queue management

Library Containers

Class	Location	Description
PlatingHistoryContainer	Library/Providers/MatterControl/	Print history
RootHistoryContainer	Library/Providers/MatterControl/	History root

Recovery

Class	Location	Description
PrintRecoveryStream	PrinterCommunication/Io/	Recovery stream